The invention refers to a two-terminal network comprising a transistor which arranged to switch from a low-ohmic to a high-ohmic state when a predetermined value of a potential drop across a collector-emitter path of the transistor is exceeded.
Whenever a transistor is arranged to pass a large current and for an economical reason is not overdimensioned there is a risk of overheating the transistor in dependence on deviations from presumed values of the current, of the transistor, of the ambient temperature etc. Regardless of whether the transistor pass the current continuously or possibly in pulses the risk for overheating can be reduced by making a collector-emitter path of the transistor quickly switch from a low-ohmic to a high-ohmic state when a predetermined maximum value of a potential drop across the collector-emitter path is exceeded.
The two-terminal network according to the invention makes its mentioned transistor quickly switch from a low-ohmic to a high-ohmic state when a predetermined value of a potential drop across its collector-emitter path is exceeded. The two-terminal network can be connected in series with a load to form a switch for the latter. A possible application of the two-terminal network is to let its transistor become a part of a power stage in an amplifier to provide it with a built-in switch.